Typical load in the metallurgical foundry industry:

Electric arc furnace: the nonlinearity and transient of the arc resistance will produce higher harmonics; when the AC furnace is running, due to the asymmetry of the three-phase arc, a negative sequence current will be generated;

Refining furnace: Compared with the electric arc furnace, the furnace condition of the refining furnace is relatively stable, there is no melting period, and the active and reactive power changes are relatively stable. Although no electric arc furnace has a great influence on the power grid, there are also very good power supply quality and power equipment. Great influence

Medium frequency furnace: The intermediate frequency furnace is a power supply device that converts the power frequency 50HZ alternating current into an intermediate frequency (300HZ to 20HZ). The three-phase power frequency alternating current is rectified into a direct current, and then the direct current is converted into an adjustable intermediate frequency current. Due to small load changes, high efficiency, less reactive fluctuations; higher power factor, but a large number of harmonics.

1. Centralized management: DBL- ATP7 series reactive power compensation device + DBL-SVG static var generator + DBL-APF series active filter (DBL-ATP7 mixed with SVG)

Terminal local management: DBL-PQ terminal power quality device

2. (Recommended) centralized management: DBL-SVG static var generator + DBL-APF series active filter

Terminal local management: DBL-PQ terminal power quality device